Box tree moth plague subsides in Dutch gardens after years of battle

The worst of the box tree moth plague appears to be over in Dutch gardens, entomologist Tymo Muus confirmed on Saturday, though the invasive caterpillar has not been eradicated entirely. Speaking to RTL Nieuws, Muus—who first identified the pest in the Netherlands in 2007—said the population surge that devastated buxus hedges across the country has now subsided. “The peak of the infestation is behind us,” Muus stated. “While we still find isolated outbreaks, the overall pressure has dropped significantly.” The decline follows years of coordinated efforts by gardeners, municipalities, and biological control programs that introduced natural predators such as parasitic wasps.

The box tree moth (*Cydalima perspectalis*) arrived in Europe from East Asia in the early 2000s and rapidly became a horticultural scourge. Its larvae devour boxwood (*Buxus sempervirens*) foliage, stripping hedges bare within weeks and leaving behind a trail of silk webbing. Dutch garden centers reported record sales of replacement plants in 2023 and 2024 as homeowners replaced decimated hedges with alternatives like Ilex crenata or Lonicera nitida. Muus noted that the current lull may be temporary, warning that “climate change and milder winters could allow the moth to rebound if vigilance wanes.”

Meanwhile, gardeners seeking sustainable solutions are turning to predator-friendly tactics. A report in *Trouw* on Saturday advises homeowners to attract natural slug and snail predators—tiger slugs, toads, and hedgehogs—to balance ecosystems and reduce reliance on chemical pesticides. “A biodiverse garden is a resilient garden,” said the article, which recommends leaving leaf litter, creating small water features, and avoiding nighttime watering to discourage slugs without harming their predators.

The box tree moth’s retreat offers a rare success story in the fight against invasive species, though experts caution against complacency. Muus emphasized ongoing monitoring, particularly in urban areas where boxwood remains popular. “We must remain alert,” he said. “The moth is still here—it’s just not winning the battle anymore.” For now, Dutch gardeners can cautiously celebrate a reprieve, even as they adapt to a landscape forever changed by an insect that once seemed unstoppable.